Register reset mechanism



Feb. 25, 1964 H. KREBsDzlo REGISTER RESET MECEANISM 2 Sheets-Sheet 1 Filed Sept. 14, 1961 4 Trai/Vf ifs' Feb. 25, 1964 H. KREBsDzlo REGISTER RESET MECHANISM 2 Sheets-Sheet 2 Filed Sept. 14, 1961 United States Patent O 3,122,315 REGISTER RESET MECHANISM Horst Krebsdzio, Peine, Hannover, Germany, assignor to- Elmeg Elektro-Mechanik G.m.b.H., Peine, Hannover, Germany Filed Sept. 14, 1961, Ser. No. 138,105 Claims priority, application Germany Sept. Z1, 1960 Claims. (Cl. 23S-144) This invention concerns improvements in or relating to impulse counters and is more particularly concerned with the mechanism for controlling'the movement of the transfer pinions provided between the digit rolls ofsuch counters.

In known impulse counters it is customary to mount the transfer pinions rotatably on a bridge like member referred to as a pinion bridge which bridge is itself pivotally mounted so as to enable it, after the commencement yof a resetting movement of the digit rolls, to pivot and thus withdraw the teeth of the pinions from engage,- ment with the means, such asdrive pins on the digit rolls. It is usual to provide a friction clutch between the pinion bridge and an actuating member, 'reset member or lever, `or another member rigidly connected to such actuating member whereby to effect movements of the pinion bridge.

If, at the end of a counting process, the digit rolls are to be returned to their starting positionsy in order to prepare the impulse counter for a new count, it is, in general, `necessary to disengage the transfer pinions, which f serve to actuate `the digit yrolls of a higher order of magother resetting members over the whole of the resetting operation. It istherefore connected withthe other resetting members by a friction clutch which, at the start of a resetting operation and prior tothe resetting movement proper to the digit rolls, immediately disengages the pinions fromjthe digit rolls, but then places them. against ak stop which limits the further movement of the pinion bridge, and thus of the pinions themselves; A slipping movement of the parts of the friction clutch with respect to one another, then permits the remaining resetting members to move further in any desired manner, without the pinion bridge, and thus the pinions, participating in such further movement.

After the resetting movement of the digit rolls to their starting positionv has been completed and upon the return movement ofthe resetting lever, the friction clutch immediately. causes the pinion bridge to move as well. The digit rolls yare now fixed in their starting position by the resetting members until the transfer pinions again make'engagement with them and hold the digit rolls in position. f

. Such known arrangements however have the disadvantage thatthe friction force acting between the two parts ofthe friction clutch is increased by the abrasionwhich unavoidably occurs during ythe operating life of such a counter. .It can thus happen, as is shown in practice, that, after the return movement ofthe digit rolls to the starting position and vthereturn movement of the resetting members have been effected, the re-engaging pinions prevent a further movement of the other resetting members totheir starting position because the friction force in the friction coupling hasbecome so high that 2 the forces provided for the return movement of such members, which forces are mostly produced by springs, do not suffice to complete the movement still required. As a result either the counter is unable to carry out further counts, or the next return movement of the digit rolls to the starting position is blocked.

It is an object of the invention to avoid or at least to reduce this disadvantage.

It might be thought that merely to increase the forces which become effective for the return movement of the resetting members would suffice. This has the disadvantage however that then the forces to beapplied for stressing the corresponding springs for the forward movement of the resetting members for carrying out resetting, would also have to be produced. A force would then have to be applied for the movement of the resetting lever, which is not practicable, particularly if the resetting movement is not manually actuated but, and this is frequently the case, is actuated by electromagnets. On the contrary, in order to keep the structural parts as small as possible, a particularly small force for the resetting movement of the digit rolls is of importance.

A very small force for initiating the resetting movement of the digit rolls could bev achieved if, in new counters, the frictional force in the friction clutch were kept so small that even after a longer operating time of the counter whenk the frictionaly force is increased by the higher abrasion, it did not rise beyond an yadmissible valuey which still ensured a satisfactory functioning of the resetting mechanism. `Against this however, is the fact that an inavoidable abrasion also occurs on the tooth side of the transfer pinions and the engagement members or drive pins on the digit roll associated therewith after a long time of operation, which increases the friction therebetween. If it is still intended satisfactorily to lift off the pinions by means of the friction clutch, the frictional force occurring in the friction clutch must not fall below a specific value. Even in new counters, this friction value has a certain amount which for satisfactory functioning limits also in these new counters the minimum value of the frictional force occurring in the friction clutch.

In such arrangements, the difiiculties thus exist that they resetting movement would have to be carried out with a minimum force inorder to be able to keep the corresponding driving elements structurally small, but must not fall below a specific initial value, if a ysatisfactory functioning of the resetting movement is to be ensured even withnew counters;

According to the invention, these diiiiculties are avoided or reduced in that during the pivotal disengaging move ment of the pinion bridge anradditional force, preferably produced by springs, is caused to act on the pinion bridge and in the direction of disengagement until the teeth of the pinions still just engage with the engagement members eg., drive pins or the like -firedly connected with the digit rolls and, afterrthe pinions have reached this position, such additional force is made inoperative on the pinion bridge by abutment against ak stop, or by the release of a spring or another force transmitting member. In other -words this means that, by means of an additional member which acts on the pinion bridge when the resetting process is started, the pinion bridge, independently of the force exerted on it by the friction clutch and supplementing said force, is movable by such a distance that its pinions are still just in engagement with the driving pins of the digit rolls. K of the pinion bridge is then effected only by the friction clutch.. s 1

This arrangement friction clutch tobe kept so low that no clamping or locking occurs even upon the return movement of the resetting The further pivoting movement enables the forces required in the members, and nevertheless a satisfactory disengagement of the pinions is achieved. The reason for this is that the forces to be applied for the movement of the pinion bridge, at once become smaller when the engagement of the pinions with the associated engagement members, drive pins or the like on the digit rolls is loosened. A relatively low force is sufficient thereafter for the further movement of the pinion bridge. This additional force which is effective only over a relatively short distance, assists .the removal of the pinions from engagement with the digit rolls. Thus the corresponding force which becomes effective in the friction clutch, can be reduced.

Such an arrangement has at least two important advantages. Firstly, a clamping or locking of the resetting members, such as has been described above, is prevented by the reduced frictional force of the friction clutch even after a long time of operation of the counter, although a satisfactory return movement is ensured; secondly, however, the reduced friction in the friction clutch reduces the abrasion which unavoidably occurs therein, and correspondingly prolongs the life of the clutch.

Experience has shown that on a counter of a particular type which was especially unsatisfactory, a life of about 20,000 reset movements was achievable with the described known constructions. After this counter was modified in accordance with the invention, satisfactory counting and resetting were still possible after 250,000 reset movements, whilst at the same time the driving force for the resetting mechanism could be reduced. After the stated number of reset movements, the tests were discontinued as the life achieved was sufficient for this difficult case,

Some preferred embodiments of mechanism according to the invention are diagrammatically illustrated in the accompanying drawings in Iwhich:

`FIGURE l is a partial somewhat schematic cross sectional view of a fir-st embodiment of a counter in accordance with the present invention, taken in a plane substantially perpendicular to the axis of rotation of the digit rolls, pinions and pivot axis of the pinion bridge, and showing the parts thereof in the position in which the pinions just engage or just re-engage the engagement members on the digit rolls;

FIGURE 2 is a partial top plan View of the counter of FIGURE 1, showing the parts thereof in the starting position;

FIGURE 3 is a partial top plan View of the counter of FIGURE l, showing the parts thereof with the pinion bridge in the disengaged condition;

FIGURES 4, and 6 are, respectively, somewhat schematic partial cross sectional views, similar to FIGURE l, of three further modified embodiments in accordance with .the present invention, and

FIGURE 7 is a partial perspective View of the counter .illustrated in FIGURES 1, 2 and 3 with certain parts :such as the spring 2, the cardioids 3 and the digit rolls 4 removed for sake of clarity.

FIGS. l, 2 and 3 are concerned with a first embodiment, omitting known parts of the counter which have Vno bearing on the invention. FIG. l shows an illustration of the entire mechanism with the housing wall removed, whilst FIGS. 2 and 3 show views of the pinion '.bridge, as seen in the direction of the arrow 17 of FIG. l. FIG. 2 thus shows the starting position of the pinion bridge in which the pinions are fully in engagement with the digit rolls, whilst FIG. 3 shows the pinion bridge in a disengaged condition. In FIG. l, the parts are shownin the position, in which the pinions just engage or just re-engage in the engagement members fixed on the digit rolls. FIG- URES 4, 5 and 6 respectively show further embodiments of the invention diagrammatically.

In FIGS. l to 3 and 7 an actuating or resetting member 1 for resetting the digit rolls of the an impulse counter to their starting position, is held in its position of rest by a spring 2 which is xedly mounted in a housing. The arm 2 of the spring engages on a pin 1 of the lever 1.

By pressing the actuating member 1 in the direction of the arrow 1S, i.e. against the force of the spring 2, a resetting movement is initiated. A cardioid 3 is fxedly connected to each digit roll 4. They serve for resetting the digit rolls 4 to their starting positions. This reset movement is effected with the aid of a reset lever 5 which, when the starting position of the corresponding digit roll is reached, engages in a recess 6 of the associated cardioid 3 and, when the digit rolls 4 are held in the starting position, has still a free movement available in the direction of actuation, in a manner which is known. Each digit roll 4, has xedly connected thereto a plurality of driving pins 7, between which the teeth of each transfer pinion 8 engage. At point 9, there is inserted in a known manner between the reset lever 5 and the upright portion 10 of pinion bridge 10, a friction clutch generally designated by reference numeral 1-6, Whose frictionally interengaging parts are pressed together by a coil spring 14. In the position of rest of the actuating lever or member 1, apin 11 mounted on the actuating lever 1, and under the inliuence of the spring 2 presses the pinion bridge 1d against a stop 12 so that the pinions 8 are held in engagement with the driving pins 7 of the digit rolls Lt. A further stop 13 limits the range of movement of the pinion bridge in the opposite direction.

The above mentioned additional force which, according to the present invention, facilitates the removal of the pinion 8 over a limited distance is produced by a leaf spring 15 in this embodiment.

If, according to FIG. l, for starting Athe resetting movement of the digit rolls 4 to their stanting positions, the actuating member `1 is pressed in the direction of the arrow 13, either by hand or by an `electrornagnet or by any other suitable means, it moves against the force of the spring 2, exerted thereon. 'Ilhe pinion bridge '19 which is inuenced by the leaf spring 15 and which, in the position of rest is pressed against the stop 12 by the pin ylill of the actuating member 1 and thus keeps the pinions 8 in engagement vwith the driving pins 7, is moved -along in the same direction upon movement of the actuating member 1 in the direction of the arrow 18 via the friction clutch 16 looated at point 9, so that the pinions 8 becomes disengaged from the driving pins 7. This disengagement is at first assisted by the leaf spring 15 until this spring assumes the position shown in FIG. 3 where it no longer bears on bridge 10. In the meantime, the pin `11 has become released from the pinion bridge 10 which `as a result, can move freely. Since this movement is at first also initiated by the leaf spring 15, the forces transmitted by the friction clutch 16 can be kept considerably lower than would necessarily be the case if the leaf spring 15 was not present. When the cooperation of the leaf spring 15 stops in the position shown in FIG. 3, the pinion bridge 14.1 can be moved further by relatively small forces. This further movement takes place until the pinion bridge abuts against the stop 13. In the meantime, return lever 5 which also moves has reached the cardioid 46 land now causes the digit rolls 4 to return to their star-ting posi-tions in a known manner, which need not be discussed in detail. In the end position, after completing the return movement proper, the ends of the return levers 5 then project deeply into the recesses 6 of the cardioids 3, and thus secure the digit rolls in position. The pinion bridge still engages on the stop 13.

Now, the return movement o-f the actuating member 1, i.e. in the opposite direction to arrow 18, takes place. Already in the first phase of movement, the pinion bridge 1@ is taken along, detached from the stop 13 and pivoted in a direction towards the digit rolls 4. This process, during which the ends of the return levers 5 slide in the recesses 6 vand still continue to hold the digit rolls 4 in their position lasts until the pinion bridge has reached the .postiion shown in FIG. l. In this position, it engages with the leaf spring 15 which, at first, prevents a .further movement of the pinion bridge. The teeth of the pinions 8 already mesh -slightly between the driving pins 7, so that .an unintentional displacement of the digit rolls is prevented. The reset lever 5 is released from the cardioid, and the friction clutch again starts to slip. Upon a further rearward movement of the actuating member 1, the pin 11 finally engages the pinion bridge 10 and, overcoming the force of the `leaf spring 15, moves it up to the stop 12. The whole return movement is thus completed. Obviously, the Whole movement of the actuating member in the direction opposite to that of arrow 18, is effected under the inftuence of the spring 2 Iwhich, therefore, most be such that it is able to overcome both the frictional forces, as well as the temporarily occurring force of the leaf spring 15. Since, when starting the return movement, the `spring 2 must be stressed, it is -of importance that the force exerted by it, is as small as possible. This can be achieved without impairing the return movement.

The advance achieved by the measures according to the invention, becomes particularly apparent when it is important that the return movement should take place very rapidly, when, for example, the return movement -is to be effected by a very rapidly acting mechanism, such as a suitably constructed electromagnet. In this case, not only the aforementioned frictional forces between the pinion teeth kand the driving pins 7 but also the mechanical inertia of the pinion bhidge with fittings must be overcome. Then the initial acceleration, produced in the present case by the leaf spring 15 Iand in other cases by other means, and which need not be transmitted via the friction clutch, is particularly advantageous. Since the return movement of the reset lever is always effected under Ithe influence of the spring 2, it is independent of the driving means. With the aid of the mechanism described, it is possible to obtain a fast return movement without being compelled to design the friction clutch correspondingly, which might have had the Idisadvantageous consequences which have `been mentioned several times. Also the spring 2 can be of small dimensions, as a result of which the structural size of the driving member for the return movement can be kept small.

The Isame advantages are enjoyed by the further embodiments by way of example now to be described all of which have the common characteristic that an additional disengagement force is caused to act rupon the pinion bridge over a limited distance, which force serves either to overcome an existing initial friction, or additionaily to overcome also the inertia forces of the pinion bridge, and does not 4load the friction clutch with correspending additional forces.

FIG. 4 shows an embodiment of the invention according to which the leaf spring 15 has been replaced by a differently shaped spring 19 which serves the same purpose as the leaf spring 15. In the starting position of the pinion bridge lil, shown in lFIG. 4, the force of the spring acts via the lin-k 20 on the pinion bridge 10a and tends .to move the bridge in the vdirection of disengagement. This action continues until the link 20 abuts against a stop 21 after a disengagement'movement of the pinion bridge 10. Starting fromthis position, the

d influence of the spring 19 on the pinion bridge 10 stops upon further movement thereof in the same direction.

The same applies likewise to the Afurther figures which show further embodiments by'way of example. Thos a spring 22 can be fixed to the actuating member 1, which, spring engages on the pinion bridge .10 when the resetting movement starts (-F-iG. y5). Thereafter it serves the same function as the springs 15 and 119 in the preceding embodiments. rWhen the pinion bridge 10 has moved back a distance which corresponds to the distance discussed with reference to FIGS. l, 2 and 3, ie. to the distance at which the teeth of the pinions S still just engage in the driving pins 7, the spring abnts against the stop 23 and thus becomes ineffective for the further movement of the pinion bridge 1i) in the same direction. y

According to FIG. 6, the above mentioned springs are replaced by a lever 24 which is hinged to the actuating lever 1 and is pressed against the pinion bridge 10 by a spring 25 which is mounted about the bearing pin 26, of the lever 24. The stop 23 has in this case the same function as the stop 23 (FIG. 5), save that in this case it engages the lever 24 and lifts it off the pinion bridge and deiiects it in the upward direction.

After the principle has been discussed, it will be apparent that further variations and modifications are possible without departing from the scope of the invention.

I claim:

l. In yan impulse counter having a plurality of digit rolls, driving means rigidly connected to said digit rolls, transfer pinions engageable with and disengageable from said driving means, a pinion bridge having said transfer pinions rotatably mounted therein said pinion bridge being pivotally mounted to eifect engagement and `disengagement: of said pinions and driving means, a reset member including friction clutch means connected between said pinion bridge and a part of said reset member and operatively associated with said pinion bridge to effect said disengagement, the improvement which comprises means serving during a pivotal disengaging movement of the pinion bridge to exert an additional disengaging force on said bridge until said pinions are only partially in engagement with said driving means, and further means serving thereupon to nullify said additional force.

2. An impulse counter as claimed in claim l in which said means exerting an additional disengaging force includes spring means.

3. An impulse counter as claimed in claim 2 in which said spring means is a leaf spring directly engageable with said pinion bridge.

4. An impulse counter as claimed in claim 2 in which said spring means is carried by said reset member and bears directly on said pinion bridge.

5. An impulse counter as claimed in claim l in which said means exerting an additional disengaging force comprises a spring-urged lever carried by said reset member and engageable directly on the said pinion bridge.

References rCited in the file of this patent FOREiGN PATENTS 71,615 France July 20, 1959 

1. IN AN IMPULSE COUNTER HAVING A PLURALITY OF DIGIT ROLLS, DRIVING MEANS RIGIDLY CONNECTED TO SAID DIGIT ROLLS, TRANSFER PINIONS ENGAGEABLE WITH AND DISENGAGEABLE FROM SAID DRIVING MEANS, A PINION BRIDGE HAVING SAID TRANSFER PINIONS ROTATABLY MOUNTED THEREIN SAID PINION BRIDGE BEING PIVOTALLY MOUNTED TO EFFECT ENGAGEMENT AND DISENGAGEMENT OF SAID PINIONS AND DRIVING MEANS, A RESET MEMBER INCLUDING FRICTION CLUTCH MEANS CONNECTED BETWEEN SAID PINION BRIDGE AND A PART OF SAID RESET MEMBER AND OPERATIVELY ASSOCIATED WITH SAID PINION BRIDGE TO EFFECT SAID DISENGAGEMENT, THE IMPROVEMENT WHICH COMPRISES MEANS SERVING DURING A PIVOTAL DISENGAGING MOVEMENT OF THE PINION BRIDGE TO EXERT AN ADDITIONAL DISENGAGING FORCE ON SAID BRIDGE UNTIL SAID PINIONS ARE ONLY PARTIALLY IN ENGAGEMENT WITH SAID DRIVING MEANS, AND FURTHER MEANS SERVING THEREUPON TO NULLIFY SAID ADDITIONAL FORCE. 